Train passengers between Northampton and London are being reminded to check for changes to their journey before travelling between May 3 and May 5.
As part of the £81m project to upgrade the rail infrastructure around Watford, Network Rail will be closing the railway line between London Euston and Watford during the May Day bank holiday weekend.
It means passengers will need to use alternative routes to travel in and out of London.
Dyan Crowther, route managing director for Network Rail, said: “The section of track at Watford is one of the most intensively used, high-speed sections in the UK and has seen tremendous growth in traffic and passengers over the last five years.
“There is never a good time to close the railway but this work is essential to maintain reliable train services for the millions of passengers who travel on this route every year.
“We have worked with all our industry partners to provide passengers with information in advance and will continue to during the work to minimise disruption as much as possible.”
The May Day weekend closure will be the first of eight weekend and bank holiday closures between May 2014 and April 2015 when significant upgrade work will be carried out to improve reliability and punctuality on the West Coast main line.
Although alternative arrangements are in place, journey times will be considerably longer and therefore passengers are being strongly advised to avoid travelling to and from London on the West Coast main line during these weekends if travel is not essential.
Barrie Cottam, London Midland’s head of West Coast services, said: “Planning of London Midland alternative travel arrangements is now complete but may be subject to late changes.
“I would advise all customers who need to make journeys along the affected route over the May Day bank holiday weekend to plan in advance and to check again before travel. Use alternative routes where possible.
“London Midland will continue to update customer information and will have staff at stations along the closed route to provide assistance over the weekend. Be prepared for longer journey times and coach replacements.”
In all cases, Virgin Trains’ customers will need to use an alternative train operator for journeys to and from London.
Those that have access to other routes via Chiltern Railways, East Midlands Trains and East Coast are being encouraged to use these instead. Southern Trains’ services will also be impacted.
As part of a joint passenger campaign, travellers should use National Rail Enquiries to check and plan their journey if they have to travel during this time using: www.nationalrail.co.uk/Watford
The confirmed dates for work on the West Coast main line at Watford are:
Saturday 3 May to Monday 5 May
Saturday 9 August to Monday 11 August
Saturday 16 August to Monday 18 August
Saturday 23 August to Tuesday 26 August
Wednesday 24 December to Monday 29 December
Saturday 14 February to Monday 16 February
Saturday 21 February to Monday 23 February
Friday 3 April to Tuesday 7 April
Network Rail had originally planned a 16-day closure in August 2014 and nine-day closure in February 2015 however after feedback from key stakeholders this strategy was revised to eight weekend and bank holiday closures resulting in less disruption for passengers using the West Coast main line.